Buggy code:
public abstract class AbstractSubsystemTest { private static final ThreadLocal < Stack < String > > stack = new ThreadLocal < Stack < String > > ( ) ; private final String TEST_NAMESPACE = "urn.org.jboss.test:1.0" ; private AbstractSubsystemTest . ExtensionParsingContextImpl parsingContext ; private List < KernelServices > kernelServices = new ArrayList < KernelServices > ( ) ; private final AtomicInteger counter = new AtomicInteger ( ) ; private final String mainSubsystemName ; private final Extension mainExtension ; private AbstractSubsystemTest . TestParser testParser ; private boolean addedExtraParsers ; private AbstractSubsystemTest . StringConfigurationPersister persister ; protected AbstractSubsystemTest ( final String mainSubsystemName , final Extension mainExtension ) { } public String getMainSubsystemName ( ) { } @ Before public void initializeParser ( ) throws Exception { } @ After public void cleanup ( ) throws Exception { } protected Extension getMainExtension ( ) { } protected String readResource ( final String name ) throws IOException { } protected List < ModelNode > parse ( String subsystemXml ) throws XMLStreamException { } protected List < ModelNode > parse ( AdditionalParsers additionalParsers , String subsystemXml ) throws XMLStreamException { } protected String outputModel ( ModelNode model ) throws Exception { } protected String outputModel ( AdditionalParsers additionalParsers , ModelNode model ) throws Exception { } protected KernelServices installInController ( String subsystemXml ) throws Exception { } protected KernelServices installInController ( AdditionalInitialization additionalInit , String subsystemXml ) throws Exception { } protected KernelServices installInController ( List < ModelNode > bootOperations ) throws Exception { } protected KernelServices installInController ( AdditionalInitialization additionalInit , List < ModelNode > bootOperations ) throws Exception { } protected static ModelNode checkResultAndGetContents ( ModelNode result ) { } protected void compare ( ModelNode node1 , ModelNode node2 ) { Assert . assertEquals ( ( ( AbstractSubsystemTest . getCompareStackAsString ( ) ) + "<seq2seq4repair_space>types" ) , node1 . getType ( ) , node2 . getType ( ) ) ; if ( ( node1 . getType ( ) ) == ( ModelType . OBJECT ) ) { final Set < String > keys1 = node1 . keys ( ) ; final Set < String > keys2 = node2 . keys ( ) ; Assert . assertEquals ( ( ( node1 + "\n" ) + node2 ) , keys1 . size ( ) , keys2 . size ( ) ) ; for ( String key : keys1 ) { final ModelNode child1 = node1 . get ( key ) ; Assert . assertTrue ( ( ( ( ( ( "Missing:<seq2seq4repair_space>" + key ) + "\n" ) + node1 ) + "\n" ) + node2 ) , node2 . has ( key ) ) ; final ModelNode child2 = node2 . get ( key ) ; if ( child1 . isDefined ( ) ) { <START_BUG> Assert . assertTrue ( child1 . toString ( ) , child2 . isDefined ( ) ) ; <END_BUG> AbstractSubsystemTest . stack . get ( ) . push ( ( key + "//" ) ) ; compare ( child1 , child2 ) ; AbstractSubsystemTest . stack . get ( ) . pop ( ) ; } else { Assert . assertFalse ( child2 . asString ( ) , child2 . isDefined ( ) ) ; } } } else if ( ( node1 . getType ( ) ) == ( ModelType . LIST ) ) { List < ModelNode > list1 = node1 . asList ( ) ; List < ModelNode > list2 = node2 . asList ( ) ; Assert . assertEquals ( ( ( list1 + "\n" ) + list2 ) , list1 . size ( ) , list2 . size ( ) ) ; for ( int i = 0 ; i < ( list1 . size ( ) ) ; i ++ ) { AbstractSubsystemTest . stack . get ( ) . push ( ( i + "//" ) ) ; compare ( list1 . get ( i ) , list2 . get ( i ) ) ; AbstractSubsystemTest . stack . get ( ) . pop ( ) ; } } else if ( ( node1 . getType ( ) ) == ( ModelType . PROPERTY ) ) { Property prop1 = node1 . asProperty ( ) ; Property prop2 = node2 . asProperty ( ) ; Assert . assertEquals ( ( ( prop1 + "\n" ) + prop2 ) , prop1 . getName ( ) , prop2 . getName ( ) ) ; AbstractSubsystemTest . stack . get ( ) . push ( ( ( prop1 . getName ( ) ) + "//" ) ) ; compare ( prop1 . getValue ( ) , prop2 . getValue ( ) ) ; AbstractSubsystemTest . stack . get ( ) . pop ( ) ; } else { try { Assert . assertEquals ( ( ( ( ( ( ( AbstractSubsystemTest . getCompareStackAsString ( ) ) + "\n\"" ) + ( node1 . asString ( ) ) ) + "\"\n\"" ) + ( node2 . asString ( ) ) ) + "\"\n-----" ) , node2 . asString ( ) . trim ( ) , node1 . asString ( ) . trim ( ) ) ; } catch ( AssertionFailedError error ) { throw error ; } } } protected String normalizeXML ( String xml ) throws Exception { } private static String getCompareStackAsString ( ) { } private void addAdditionalParsers ( AdditionalParsers additionalParsers ) { } private void validateDescriptionProviders ( AdditionalInitialization additionalInit , KernelServices kernelServices ) { } private final class ExtensionParsingContextImpl implements ExtensionParsingContext { private final XMLMapper mapper ; public ExtensionParsingContextImpl ( XMLMapper mapper ) { } @ Override public void setSubsystemXmlMapping ( final String namespaceUri , final XMLElementReader < List < ModelNode > > reader ) { } @ Override public void setDeploymentXmlMapping ( final String namespaceUri , final XMLElementReader < ModelNode > reader ) { } private XMLMapper getMapper ( ) { } }

Fix:
Assert . assertTrue ( ( ( ( ( ( "key=" + key ) + "\n<seq2seq4repair_space>with<seq2seq4repair_space>child1<seq2seq4repair_space>\n" ) + ( child1 . toString ( ) ) ) + "\n<seq2seq4repair_space>has<seq2seq4repair_space>child2<seq2seq4repair_space>not<seq2seq4repair_space>defined\n<seq2seq4repair_space>node2<seq2seq4repair_space>is:\n" ) + ( node2 . toString ( ) ) ) , child2 . isDefined ( ) ) ;